Two problems related to brake master cylinder have been reported for the 2005 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Toyota Sienna based on all problems reported for the 2005 Sienna.
2005 Toyota Sienna. Consumer writes in regards to brake failure. The consumer stated several weeks ago, he was turning around in the driveway, and when he pressed down with his right foot, the engine roared and the vehicle jumped forward until he applied more pressure to the brake pedal, at which point the vehicle stopped. The consumer realized the brake pedal could be depressed easily below the level of the gas pedal, hence the roar and surge. The consumer was informed brake pedals were no longer adjustable and when the mechanic checked the vehicle, the brake master cylinder was failing and accounted for the brakes not functioning properly at times.
Last year I was driving my 2005 Toyota Sienna, and a line of ducks walked out in front of my car. I slammed on the brakes but the car just kept going, running over a duck and stopping about 30 ft later. I thought maybe I was too slow to brake. Then a couple of weeks later a man walked out from behind a trailer and I tried to slam on the brakes (I was only going about 20 mph). The man saw me and had time to get out of the way thankfully since the car didn't stop until 10 ft afterwards. I brought the car to my dealer and they said 'the master cylinder is bypassing' and replaced it. I don't have the old part. However, I wanted to make sure you knew about it, because it was not obvious during normal driving, only when I had to stop quickly. And someone could easily have been killed.